Lens cover device for telescopic sights



March 24, 1953 c. A. BLAIS, SR

LENS COVER DEVICE FOR TELESCOPIC SIGHTS Fil ed June 17, 1952 PatentedMar. 24, 1953 srrs TNT OFFICE LENS COVER DEVICE FOR TELESCOPIC SIGHTSClemence A. Blais, Sr., East Moline, Ill.

Application June 1'7, 1952, Serial No. 293,998

This invention relates generally to telescopic gun sights and moreparticularly to protective covers for the lens of such sights.

While it has been proposed that covers be provided to protect the lensof telescopic gun sights from dirt, dust and moisture, to besatisfactory these protective covers necessarily should beinstantaneously operable with the minimum of effort on behalf of therifleman. It is therefore an object of this invention to provide animproved lens cover device for telescopic gun sights, which device isquickly operable by the riileman with the minimum of efiort during hisconventional handling of the ride.

It is important to the keeping of the telescopic lens clear and cleanthat the lens be uncovered substantially only as long as the rifiemanactually is making use of the sight. Accordingly, another object of thisinvention is to provide for the front and rear lens covers of atelescopic sight to be quickly and rapidly movable by a simple singlethumb or finger operation to both their open positions and their closedpositions even while the rifle is shouldered in firing position.

Disadvantages of prior lens protective cover devices not only relate totheir operation but to the number and kinds of parts required. Suchparts include coil springs and latches that require special handling oroperation, and these ports may weaken or break making the devicecompletely inoperative. Hence, it is a further object of this inventionto make the front and rear lens cover device with relatively simple,inexpensive parts that may be quickly and easily assembled to be apermanent attachment to the sight with little likelihood thatreplacement or adjustment of any of the parts will be necessary.

Still another object is to provide for such device a finger tip controlwhich eases or sort of snaps the covers to either their closed or openpositions with the covers, in effect, locked in either of thosepositions by a relatively large frictional force that must be overcomein effecting rotational movement of the covers from either of thosepositions.

Still another object of this invention is to provide in an improved andsimplified telescopic sight cover device of parts that may be standardized for permanent attachment to telescopic sight tubes which areadjustable by shortening or extending the tube length for focaladjustment.

It is also an object of thi invention to permanently attach to atelescopic gun Sighta lens cover device which, when in closed position,sub- Claims. (Cl. 33-50) s-tantially seals the lens from dust andmoisture.

These and other objects and advantages of this invention will becomeapparent to those skilled in the art, from the following description conidered in connection with the accompanying drawing in which: Y

Fig. 1 is a perspective view of a telescopic gun sight having anattached lens cover device embodying this invention, with the coversshown closed;

Fig. 2 is a perspective view of the telescopic gun sight of Fig. 1 withthe attached lens covers shown in open position;

Fig. 3 is a sectional view taken transverse the telescopic tube throughthe tension band desi nated 3 l the lens covers being closed;

Fig. 4 is a sectional view similar to that of Fig. 8, only the lenscovers are intermediate their closed and open positions;

Fig. 5 is also a sectional view similar to that of Fig. 3, however takenwhen the lens covers are in their open positions;

Fig. 6 is an. enlarged fragmentary, sectional view of the end portion ofthe telescopic sigh-t tube and one lens cover;

' Fig. 7 is a sectional view taken through the eccentric designated 30in Fig. 1; and

Fig. 8 is a schematic view illustrating the lens cover thumb operatingcontrol in its different positions corresponding to the differentpositions of the lens covers.

A telescopic gun sight to which an embodiment of the subject lens coverdevice is attached is illustrated in Fig. 1 and comprises tube H whichhas lens (not shown) disposed in the front and rear ends thereof. Tubelength adjustable means i2 provides for focusing the sight. At the frontand rear ends of the tube there are split bands, It and I l, each ofwhich is clamped about an end of the tube by suitable fastening meanssuch as nut l6 and bolt ll. Each of those bands has an extending tab, l3and i9 respectively, in which the opposite end portions of pivot rod 2:are journaled. The pivot rod 2| is disposed alongside of tube II withthe axes of the rod and the tube having fixed positions parallel to eachother. The end portions of the operating rod extend through the tabs,and covers 22 and 23 are fixedly attached to the respective ends of therod by any suitable means such as a machine screw 24%.

An operating cylinder 30 is attached to the pivot rod between thejournaled ends thereof.

The exact position of this operating cylinder along the rod depends onthe desire of the riflepose, in this instance there is provided atension band 3| made of resilient material such as spring steel. Thisband has a middle, C-shaped portion 32 which is generally circular incross section and which loosely encircles tube II and i'siree to turnabout the tube while yet beingself held thereon except for movementlongitudinally of the tube. The tension band has laterally extending endportions, 33 "and 34, which are substantially parallel to each other andwhich are spaced apart a distant equal to the diameter of theopera-tingcylinder. End tips, 35 and 3B, of these end portions arecurved on the are of the cylinder surface so as to be turned inwardlytoward each other bringing those tips closer together than are thesubstantially parallel portions. The operating cylinder is snuglydeposed between the end portions of the tension band with the axis ofthat cylinder more remote from the tube axis than is the pivot rod.

Suitable means is incorporated in the operating cylinder and tensionband to prevent the tension band from moving longitudinally of the tubeand away from the cylinder. Yet this means does not interfere with thetension band coacting with the operating cylinder. In this instance,this means comprises collars 4H, 42,

disposed at the opposite ends of the operating cylinder. The operatingcylinder therefore has an H-shaped longitudinal cross section (Fig. 7),and these collars are axially spaced so the'middle cylindrical portionof the cylinder has suincient length to accommodate the width of the endportions 33, Not the tension band, thereby holding or retaining thetension band in contact with the operating cylinder. The collars M, 52have knurled peripheries turning the cylinder by the thumb.

So that the parts may be standardized. for telescopic sights which areshortened or extended to different lengths, at least one clamping bandH! has suificient axial length (Fig. 6) that it may extend beyond the adistance at least equal to the justinent.

As is also best shown in 6, the covers and clamping bands cooperate tosubstantially seal the ends of the tube to protect the lens. a The upperhalf of the periphery of each cover is bent at a right angle to its faceto comprise a flange tube length ad- 48 that overlays the end part 01"the upper half.

of the associated clamping band, the lower half l! of the periphery ofeach cover is tapered and closely fits the lower half ii;- of theperiphery of the associated clamping band, as. this lower half 48 of theclamping band extends to facilitate end of tube it 4 dent. In moving thecovers from their closed positions to their open positions, the rod isrotated through an angle sufficiently large that, in the open position,the covers are completely away from the telescopic sight and do notinterfere with the proper use of the sight. Preferably, this angle ofrotation is approximately 135 degrees. The function and operation of theeccentric cylinder and tension band may be most easily explained inconnection with schematic view of Fig. 8.

Numeral 5| designates the axis of tube II, and 52 is the axis of thepivot rod. The circles or'c'onstruction lines 53, 5d and 55 representthe closed, intermediate and open positions, respectively,.of: theeccentric operating cylinder which pivots about axis 52. This eccentric,operating cylinder'is placed so that its center moves in an arcv 56about the pivot rod axis remote from the tube ll.

Arc 58 is generated by motionof the center of the operating cylinder inits movement from closed to open positions; this are is drawn with axis52 as a fixed center since the tube axis and pivot rod axis have norelative movement. In Fig. 8 another are 5? is drawn which has tube axis5! as a center and which has a radius equal to the distance from axis stto the center of the operating cylinder when it is. in either the openor closed positions. This are therefore cuts through points on arc 58corresponding to the center of the operating cylinder in the open andclosed positions.

The distance 55 betweenarcs 55 and 5? corresponds to the lateralmovement of the center of the operating cylinder away from the tube axis5i as the operating cylinder moves from one position to the other.

Since the tension band is. loosely disposed about tube ii and is free tomove thereon under the influence of the operating cylinder, the ends ofthe tension band are always a. constant distance from the tube axis 5|although they do have movement circuinierentially which is caused by theeccentric operating cylinder as shown by Figs. 3 to 5.

sion band are curved inwardly toward each otherand contact the outersurface of the operating cylinder. And with the center or axis of theoperating cylinder being. spaced farthest from the tube axisintermediate the closed and open positions, it necessarily results thatthere is movement of the cylinder relative to the end. tips of thetension band. As mentioned those tips stay a fixed distance from thetube axis, and the cylinder moves with respect to that axis. Because ofthis relative movement the cylinder forces the end tips apart flexingthe tension band, appreciably increasing the friction, binding orclamping or" the tension band on the cylinder. This flexing of thetension band to increase the friction or bindingv of the cylinder isquite noticeable even immediately adjacent the'closed or open positions.This is illustrated byv the appreciable increase in distance betweenarcs 5S and 51 even near the closed and open positions.

In the. closed and open positions, however, the tension band is in arelatively unflexed state. Thus, the intermediate position flexing andfrictional binding efiects a substantial locking means. for the coverstokeep them in. their selected closed or cpenpositicns thereby preventinginadvertent or accidental movementof the covers when the rifle isjerked or jarred in handling.

Also this flexing and unfiexing of the tension band results in an easingor sort of snap of the covers into both their closed and open positions,but this snap or easing into position does not occur until thosepositions are nearly reached while turning the operating cylinder.

Although but one embodiment of this invention is shown and described, itwill be realized that variations and modifications thereof may be madeby skilled persons without departing from the scope of the inventiondefined by the appended claims.

It is claimed and desired to secure as Letters Patent:

1. A lens protector for a telescopic gun sight tube, comprising anoperating rod having its axis fixedly disposed parallel to the gun sighttube, means connecting said rod to said tube with said rod rotatableabout its axis, a front lens cover fixedly attached to a first end ofsaid rod, a rear lens cover fixedly attached to the opposite end of saidrod, rotation of said rod through a predetermined angle about its axismoving said covers from closed positions to open positions with respectto said tube, eccentric means fixedly attached to said rod, resilientmeans secured to said tube and contacting said eccentric means, saidresilient means being substantially unfiexed when said covers are insaid closed and open positions and being flexed by said eccentric meanswhen said covers are intermediate said closed or open positions tofrictionally bind said eccentric means, whereby said covers aresubstantially locked in any selected position by the coaction of saideccentric means with said resilient means.

2. A lens protector for a telescopic gun sight tube, comprising anoperating rod having its axis fixedly disposed parallel to the gun sighttube, a first tube band clamped to one end of said tube and having alateral tab in which a first end of said rod is journaled, a second tubeband clamped to the opposite end of said tube and having a lateral tabin which the opposite end of said rod is journaled, a first lens coverfixedly attached to said first end of said rod, a second lens coverfixedly attached to said opposite end of said rod, whereby rotation ofsaid rod through a predetermined angle moves said covers from theirrespective closed positions to their respective open positions, acontrol cylinder fixedly attached to said rod intermediate its said endswith the axis of said cylinder parallel to and spaced from the axis ofsaid rod whereby the axis of said cylinder in turning about said axis ofsaid rod defines the arc of a circle and has lateral movement withrespect to said axis of said tube, a generally C-shaped tension band ofresilient material having a middle portion loosely encircling said tubewith substantially parallel end portions extending laterally of saidtube and contacting opposite sides of said cylinder whereby said tensionband is slidable about said tube responsive to turning of said cylinder,said cylinder disposed between said parallel lateral portions atpositions corresponding to said closed and said open positions of saidcovers, the ends of said portions being curved inwardly toward eachother contacting the surface of said cylinder, said cylinder beinglaterally more distant from said axis of said tube at positionscorresponding to positions intermediate said closed and open positionswhereby said inwardly curved ends are forced apart by said cylinderflexing said tension band and causing frictional binding of saidcylinder to prevent accidental turning of said cylinder and displacementof said covers from their said open or closed position.

3. A lens protector as claimed in claim 2 wherein said cylinder has twoaxially spaced collars with said lateral end portions being disposedbetween said collars to restrain said tension band from moving axiallyof said tube.

4. A lens protector as claimed in claim 2 wherein retaining meanscooperates between said cylinder and said tension band restraining saidtension band from moving axially alon said tube.

5. A lens protector as claimed in claim 2 wherein one said tube has acylindrical portion extending beyond the end of said tube to which saidone tube band is clamped to accommodate for adjustment of the length ofsaid tube.

6. A lens protector for a telescopic gun sight tube, comprising anoperating rod having its axis fixedly disposed parallel to the gun sighttube, a front tube band clamped to one end of said tube and having a tabin which a first end portion of said rod is journaled, a rear tube bandclamped to the opposite end of said tube and having a tab in which thesecond end portion of said rod is journaled, a front lens cover fixedlyattached to the first end of said rod, a rear lens cover fixedlyattached to the opposite end of said rod, whereby rotation of said rodthrough a predetermined angle moves said covers from their respectiveclosed positions to their respective open positions, a control cylindereccentrically fixed to said rod whereby said axis of said cylinder inturning about said axis of said rod has lateral movement with respect tosaid axis of said tube, a tension band being disposed loosely about saidtube with a portion thereof extending laterally of said tube andfrictionally contacting said cylinder whereby said tension band holdssaid covers in any selected position, said cylinder having retainingmeans cooperating with said portions of said tension band restrainingsaid tension band from moving axially of said tube.

7. A lens protector as claimed in claim 6 wherein the upper halfperipherial edge of each of said covers is flanged and overlaps theupper edge 01' the corresponding said tube band, and the lower halfperipherial edge of each of said tube bands extends axially beyond theupper edge thereof and is formed to interfit closely with the bottomhalf edge of the corresponding said cover, whereby said covers cooperatewith said tube bands to seal the ends of said tube.

8. A lens protector as claimed in claim 6 wherein one said tube band hasa cylindrical portion extending beyond the end of said tube to whichsaid one tube band is clamped to accommodate for adjustment of thelength of said tube.

9. A lens protector as claimed in claim 6 wherein said retaining meanscomprises two axially spaced collars on said cylinder between which saidportion of said tension band are disposed.

10. A lens protector as claimed in claim 6 wherein one said tube bandhas a portion extending beyond the end of said tube to which said onetube band is clamped to accommodate for adjustment of the length of saidtube, and said retaining means comprises two axially spaced collars onsaid cylinder between which said portions of said tension band aredisposed.

CLEMENCE A. BLAIS, Sn.

N 0 references cited.

